2853.90.10.00 - Of copper (phosphor copper), containing more than 15 percent by weight of phosphorous

This HTS category, 2853.90.10.00, specifically classifies phosphides of copper that contain more than 15 percent by weight of phosphorus. These materials are typically used in metallurgy, particularly for brazing and soldering applications, due to their fluxing properties and ability to create strong metallurgical bonds. The high phosphorus content is a critical determinant for inclusion in this subheading.

It is important to distinguish this category from its sibling, 2853.90.50.00, which covers phosphides of other metals or nonmetals. While both relate to phosphides, the defining factor for 2853.90.10.00 is the specific presence of copper and the high percentage of phosphorus. For example, phosphides of aluminum or silicon would fall under the sibling category, whereas phosphor copper fitting the phosphorus content criteria belongs here.

As this subheading represents a leaf node in the HTS structure, there are no further subcategories. Classification is therefore determined by the material composition (copper) and the precise phosphorus content exceeding 15 percent by weight. Importers should ensure accurate chemical analysis to verify compliance with these specific criteria for correct classification and duty assessment.